Hey all, looking at some wheels,

http://www.ebay.com/itm/18-..._Accessories&vxp=mtr

Do these look like they will work? 20mm offsets front and rear 18x8.75 18x9.75

-Alex

Definitely won't fit correctly. Looking at the fronts only, those 8.75" wide wheels would need a 72mm offset if you wanted the street side of the wheel to be at the same location as the stock wheels. Since they've only got a 20 mm offset, they would stick out 52mm (or 2") further than stock.

quote Originally posted by FieroGTRwideboby: ... Do these look like they will work? 20mm offsets front and rear 18x8.75 18x9.75 -Alex

That combo definitley not. Too greedy with width But you can do the 18x8.75 35mm rear and the 17x7 38mm front which they both have and I guarranty they will fit and look awesome.

Alex4mula,

How about 18x7.5 38mm and 18x8.75x 35mm??

I can get them in that combo. Thanks for the help.

-Alex

Subjective opinions are easy... the trouble is that everyone has different tastes. If you'd like me to modify a pair of my '88 suspension drawings (front and rear) for you to see objectively how they will fit, then post the tire sizes you plan to mount on those wheels and you can decide for yourself whether they'll look good.

225/40/18 front
265/35/18 rear

-Alex

Coilovers or stock springs? Lowered or stock height?

front lowering springs (WCF) and rear coilovers

Since you didn't specify how much of a drop you've done to the suspension, I drew out the stock spring height on both the front and rear. You'll have to subtract whatever your drop height is from the vertical numbers in both drawings to get your actual vertical clearances. Here's the front depiction where the stock wheels, tires, and dimensions are in blue and the new wheels and their effects in red;



Here's a synopsis of what you're looking at in the front using those wheels and tires:

1. overall a good wheel and tire choice
2. the overall ground clearance improves by about 20 mm despite the tire diameter difference being less than that since the sidewalls are stiffer on the new tires;
3. the vertical fender clearance to the tire gets smaller by about 8 mm (I only drew in the upper framerail so to get your actual fender clearance you'll need to measure how much lower the fender opening is from the framerail);
4. the minimal sidewall bulge in these tires partly compensates for the lack of offset in the wheels, though the tires will stick out about 10 mm past the stock location on the roadside face of the wheels;
5. the center of the tire patch remains within 1 mm of the stock tires so your scrub radius won't change (a good thing);

And here is the schemtic of the rear wheel and tire choice. Again, the stock wheel and tire are in blue and your new option in red (I hadn't noticed you posted that you had coilovers... regardless, this tire combo fits with the stock springs so it will certainly fit with the coilovers:



Here are my observations with this combo:

1. I have not drawn in the wheel camber which should be neg 1 degree. That will tuck the top of the tire in by about 10 mm but will still result in the tires bulging outward by about 23 mm past stock;
2. the wheel may be too narrow for the tire since most tire websites recommend using a 9.5" wide wheel with a 265 tire. For example, Goodyear will not honor their warranty unless the wheel width is at least 9" for this size tire;
3. the overall ground clearance improves by about 20 mm despite the tire diameter difference being much less than that since the sidewalls are stiffer on the new tires;
4. the vertical fender clearance to the tire gets smaller by about 5 mm;
5. the center of the tire patch will move inwards by an insignificant 5 mm;
6. the tire will clear the trailing link.

Hope this helps.

Thanks for the advice, everything seemed to work out brilliantly. I got the WCF coilover kit, and the 13" brake kit from Fieroguru, so naturally got the XXR wheels... Went with the 18x7.5 x 38m and 18x8.75 x 35mm . For the tires I did 225/40/18 and 265/35/18, not rubbing or anything. Thanks for the help!

Alex -

Told you they will fit. They look great! And now you have real meat back there

Looks good, but man, those 18" wheels make even the 13" brakes look small! Can you post a picture of the rear view (not a rear quarter view) of the car sighting down one side on a very shallow angle? And another one from the front view with the wheels turned straight ahead, sighting down one side at a shallow angle? Do you know what camber angle you have on the rear and front wheels?

[This message has been edited by Bloozberry (edited 06-28-2012).]

That's all I took, I can take some more and post up too Thanks again for the help. They are just right.. I was worried they might protrude from the body... Also tucked them in about 2.4 mill with the rotor hats, since they are thinner than the stock fiero rotors.


Alex

As far as camber, not sure the fronts def have a bit, rears have not been touched since lowered with coilovers. ??

[This message has been edited by FieroGTRwideboby (edited 06-28-2012).]

Glad it worked out. I was a bit surprised at how well the rears remained inside the fender too. But then if you lowered the car 1" without readjusting the wheel alignment, then your tires would tuck in about 19mm more than my drawing shows above, including the extra bit for the rotor hat differences. If you lowered the car 1.5" then you'd get the wheel tops tucked in by 21 mm more than shown, and with a 2" drop you'd get 25 mm more tuck in at the top. That probably explains why they fit better than my drawing shows... well, that and the fact that I used a generic wheel cross section with an approximated tire cross section.

My experience is that those diagrams (yours, Thorma's, etc.) exagerate the issues a lot. They always look good. Lowered even better.

Perhaps, but to me it looks like both front and rear tires on FieroGTRwidebody's car stick out beyond the fender edges even with his self-admitted out of spec camber (no offense intended). His last photo is more telling than the "directly above" photos which are angled to make the wheels appear more tucked in. That coupled with too much camber (on the rear tires and likely on the front too) I suspect that Joe's and my drawings are less exaggerated than you say.

Pictures lie some too. But I think some like/want a perfect tucked in fit which is very difficult to get with the moderately priced (meaning non custom) wheels out there specially if you want the widest wheels possible. In many nice Fieros with aftermarket wheels the front or rear may stick out a little bit. Most people like it anyway, don't notice and do go pointing it out. I say this for new people out there to not take these diagrams to the exact milimeter and not buy a nice wheel set because of few milimeters. It is a nice guide but at the end ask others who may have the same wheel specs and have better decision facts.

Will 18x8.5 +48mm offset work on front and rear of '88 GT?
the rear has coilovers
the front will have Fiero Warehouse wide front fenders.

thanks...

Edit: another option for rear 18x9.5 +38mm offset.

[This message has been edited by Tom Slick (edited 10-15-2013).]